Use [[maybe_unused]]

samples/geotag.cpp

@@ -22,7 +22,6 @@
 // g++ geotag.cpp -o geotag -lexiv2 -lexpat
 
 #include <exiv2/exiv2.hpp>
-#include "unused.h"
 
 #include <filesystem>
 #include <iostream>

samples/xmpsample.cpp

@@ -21,7 +21,6 @@
 // Sample/test for high level XMP classes. See also addmoddel.cpp
 
 #include <exiv2/exiv2.hpp>
-#include "unused.h"
 
 #include <string>
 #include <iostream>
@@ -77,26 +76,22 @@ try {
     assert(xmpData["Xmp.dc.one"].toInt64() == -1);
     assert(xmpData["Xmp.dc.one"].value().ok());
 
-    const Exiv2::Value &getv1 = xmpData["Xmp.dc.one"].value();
-    UNUSED(getv1);
+    [[maybe_unused]] const Exiv2::Value &getv1 = xmpData["Xmp.dc.one"].value();
     assert(isEqual(getv1.toFloat(), -1));
     assert(getv1.ok());
     assert(getv1.toRational() == Exiv2::Rational(-1, 1));
     assert(getv1.ok());
 
-    const Exiv2::Value &getv2 = xmpData["Xmp.dc.two"].value();
-    UNUSED(getv2);
+    [[maybe_unused]] const Exiv2::Value &getv2 = xmpData["Xmp.dc.two"].value();
     assert(isEqual(getv2.toFloat(), 3.1415f));
     assert(getv2.ok());
     assert(getv2.toInt64() == 3);
     assert(getv2.ok());
-    Exiv2::Rational R = getv2.toRational();
-    UNUSED(R);
+    [[maybe_unused]] Exiv2::Rational R = getv2.toRational();
     assert(getv2.ok());
     assert(isEqual(static_cast<float>(R.first) / R.second, 3.1415f ));
 
-    const Exiv2::Value &getv3 = xmpData["Xmp.dc.three"].value();
-    UNUSED(getv3);
+    [[maybe_unused]] const Exiv2::Value &getv3 = xmpData["Xmp.dc.three"].value();
     assert(isEqual(getv3.toFloat(), 5.0f/7.0f));
     assert(getv3.ok());
     assert(getv3.toInt64() == 0);  // long(5.0 / 7.0)
@@ -104,10 +99,9 @@ try {
     assert(getv3.toRational() == Exiv2::Rational(5, 7));
     assert(getv3.ok());
 
-    const Exiv2::Value &getv6 = xmpData["Xmp.dc.six"].value();
-    UNUSED(getv6);
+    [[maybe_unused]] const Exiv2::Value &getv6 = xmpData["Xmp.dc.six"].value();
     assert(getv6.toInt64() == 0);
-    assert(getv6.ok());
+    assert(getv6.ok()^);
     assert(getv6.toFloat() == 0.0f);
     assert(getv6.ok());
     assert(getv6.toRational() == Exiv2::Rational(0, 1));
@@ -117,8 +111,7 @@ try {
     getv7.toInt64(); // this should fail
     assert(!getv7.ok());
 
-    const Exiv2::Value &getv8 = xmpData["Xmp.dc.eight"].value();
-    UNUSED(getv8);
+    [[maybe_unused]] const Exiv2::Value &getv8 = xmpData["Xmp.dc.eight"].value();
     assert(getv8.toInt64() == 1);
     assert(getv8.ok());
     assert(getv8.toFloat() == 1.0f);

src/CMakeLists.txt

@@ -34,7 +34,6 @@ add_library( exiv2lib_int OBJECT
     tiffimage_int.cpp       tiffimage_int.hpp
     tiffvisitor_int.cpp     tiffvisitor_int.hpp
     tifffwd_int.hpp
-    unused.h
     utils.hpp               utils.cpp
 )
 

src/bmffimage.cpp

@@ -14,7 +14,6 @@
 #include "tiffimage.hpp"
 #include "tiffimage_int.hpp"
 #include "types.hpp"
-#include "unused.h"
 
 // + standard includes
 #include <cassert>

src/convert.cpp

@@ -16,7 +16,6 @@
 #include "xmp_exiv2.hpp"
 #include "futils.hpp"
 #include "convert.hpp"
-#include "unused.h"
 
 // + standard includes
 #include <algorithm>

src/crwimage_int.cpp

@@ -3,7 +3,6 @@
 #include "crwimage_int.hpp"
 #include "canonmn_int.hpp"
 #include "i18n.h"                // NLS support.
-#include "unused.h"
 #include "error.hpp"
 #include "enforce.hpp"
 
@@ -592,8 +591,7 @@ namespace Exiv2::Internal {
     {
         CrwDirs crwDirs;
         CrwMap::loadStack(crwDirs, crwDir);
-        uint16_t rootDirectory = crwDirs.top().crwDir_;
-        UNUSED(rootDirectory);
+        [[maybe_unused]] uint16_t rootDirectory = crwDirs.top().crwDir_;
         assert(rootDirectory == 0x0000);
         crwDirs.pop();
         if (!pRootDir_) {
@@ -671,8 +669,7 @@ namespace Exiv2::Internal {
         if (pRootDir_) {
             CrwDirs crwDirs;
             CrwMap::loadStack(crwDirs, crwDir);
-            uint16_t rootDirectory = crwDirs.top().crwDir_;
-            UNUSED(rootDirectory);
+            [[maybe_unused]] uint16_t rootDirectory = crwDirs.top().crwDir_;
             assert(rootDirectory == 0x0000);
             crwDirs.pop();
             pRootDir_->remove(crwDirs, crwTagId);

src/preview.cpp

@@ -18,7 +18,6 @@
 #include "jpgimage.hpp"
 #include "tiffimage.hpp"
 #include "tiffimage_int.hpp"
-#include "unused.h"
 
 // *****************************************************************************
 namespace {

src/types.cpp

@@ -6,7 +6,6 @@
 #include "futils.hpp"
 #include "i18n.h"  // for _exvGettext
 #include "safe_op.hpp"
-#include "unused.h"
 
 // + standard includes
 #include <string>

src/unused.h

@@ -1,8 +0,0 @@
-// SPDX-License-Identifier: GPL-2.0-or-later
-
-#ifndef UNUSED_H
-#define UNUSED_H
-
-#define UNUSED(x) (void)(x)
-
-#endif // UNUSED_H

src/value.cpp

@@ -6,7 +6,6 @@
 #include "enforce.hpp"
 #include "error.hpp"
 #include "convert.hpp"
-#include "unused.h"
 
 // + standard includes
 #include <ctype.h>
@@ -451,8 +450,7 @@ namespace Exiv2 {
         std::string c = value_;
         if (charsetId() == unicode) {
             c = value_.substr(8);
-            const size_t sz = c.size();
-            UNUSED(sz);
+            [[maybe_unused]] const size_t sz = c.size();
             if (byteOrder_ == littleEndian && byteOrder == bigEndian) {
                 convertStringCharset(c, "UCS-2LE", "UCS-2BE");
                 assert(c.size() == sz);